But in school systems with high arrest rates, such as New London and Norwich, the group concludes that some of the behavior that led to the arrests might not necessarily be criminal and could have been handled by the school without police involvement. The group is calling for reforms that would keep more children in school and fewer in the juvenile justice system.

The study also concludes that "arrest rates are much higher for students of color, students in poor districts, and special education students," and that black and Hispanic students are three times more likely to be arrested than white students.

The study says the New London school system reported 71 arrests during the 2010-11 school year and ranked third-highest statewide in arrests per 1,000 students. It reports that Bennie Dover Jackson Middle School in New London, with 42 arrests among the 590 students, ranked ninth on the list of individual schools with the highest arrest rates in the state.

The sheer number of arrests puts Bennie Dover at No. 13 among all schools for total arrests, sharing company with schools in Meriden, Bridgeport, New Haven and New Britain, some of which have more than twice the school population.

Superintendent Nicholas Fischer said the numbers are simply not credible. He said a school database that tracks student arrests shows just 15 arrests during the year covered by the study.

"I question the accuracy of their reporting," Fischer said. "I'm not sure what they mean by an arrest."

Sarah Esty, who conducted the study, said arrests — for the purposes of the study — include data provided to the state Department of Education by the schools as part of an ED166 form, a school disciplinary report. The state requires the schools to report whether a serious school incident resulted in an arrest, on or off school property.

Esty said that determining the number of arrests is an imperfect science since the state lacks legislation requiring a standardized definition of student or school-based arrests. While a school staff member may see a student taken away by police, they would not necessarily know whether the student actually was arrested, diverted to a juvenile review board or ended up in court and with a criminal record.

'Top targets for intervention'

The Norwich and New London school systems, along with Norwich Free Academy, were each cited in the study as districts that "present top targets for intervention."

The Norwich school district ranked 11th in the state with 46 arrests — 12.1 per 1,000 students. Norwich Free Academy ranked 12th with 28 arrests — or 11.8 per 1,000 students.

Students are arrested in schools for a number of reasons, from possession of weapons or drugs to skipping class or using profanity. The most common reason for arrests in 2011 — the rationale for 21 percent (672) of all student arrests — was a fight or physical altercation that resulted in minor injuries to at least one party, according to the study.

Drug- and alcohol-related offenses comprise the second-largest category of incidents leading to student arrests, accounting for approximately one in five, 19 percent of the arrests made in 2011. Other charges included weapons possession and school policy violations such as using profanity, skipping class or disruptive behavior.

Norwich schools Superintendent Abby Dolliver also was surprised at the high number of arrests attributed to her district, and said that, at the time of the study, the school system operated both an alternative high school, Thames River Academy, and the Deborah Tennant-Zinewicz School, a clinical day school run by Natchaug Hospital for kids with emotional or behavioral problems.

The former Thames River Academy, with an enrollment of 87 students, accounted for eight arrests in the 2010-11 school year, according to the study.

Dolliver said she expects the number of arrests to decline not only with the availability of school resource officers at the middle schools, but also with new policies that allow staff to contact parents and not necessarily police every time a student leaves school grounds.

Fischer, the New London superintendent, said schools do an enormous amount of behind-the-scenes work with students and their parents, involving social workers and a juvenile review board, all in an effort to intervene and keep students out of trouble and in school. Many of the students arrested face challenges at home that could include physical and sexual abuse, unstable households, depression and traumatic events that lead to troubles in daily life.

"We do everything in our power to avoid arresting students … all kinds of steps to address numerous situations," Fisher said.

Both the Norwich and New London districts have uniformed school resource officers. New London, which at one time had three, now has just one. Norwich has one at each of its middle schools.

'A holistic approach'

Norwich Police Capt. Patrick Daley said he believes the presence of the officers in the schools helps stem the number of arrests.

"They intervene in problems before they escalate," Daley said. "They also work hand in hand with school staff and social workers for a holistic approach to at-risk students. They're not just armed security guards … they're getting to know the students. An arrest has always been the last resort."

Esty said the notion of school resource officers preventing crimes runs counter to national data that shows the presence of police leads to an increase in the number of arrests for lower-level offences. But better-trained officers might have the opposite effect, she said.

There were some bright spots in the study. Overall, student arrests continued to drop from a high of 3,396 in 2008 to 2,936 in 2011. Of the state's 1,116 public schools, 787 reported zero arrests.

The study cites a 2007 law limiting use of out-of-school suspensions as raising awareness of discipline practices.

Among middle-income rural and suburban districts cited as positive examples were Lisbon and East Granby, each with no student arrests. East Lyme, Ledyard, Old Saybrook, North Stonington and Westbrook were among school systems with two or fewer arrests per 1,000 students.

"Arrest increases the likelihood of dropout, as well as a host of other negative life outcomes with significant financial and social harm on both the individual and his community," the study says. "The entire state suffers from decreased lifetime earnings, increased risk of future incarceration and greater likelihood of relying on state-funded programs."